Interpretive Summary: The high economic potential makes cotton a desirable crop outside of the soils it was native to, which means it sometimes encounters flooding conditions. Cotton is poorly adapted to water-logged soils, and the objective of this research was to identify differences among cotton varieties in their tolerances to flooded soil conditions. Differences were observed among cotton varieties, but more study is needed to identify varieties that perform satisfactorily under flooded soil conditions, if any exist. The findings of this research will assist farmers in the US and other parts of the world who suffer yield reductions each year due to excessive, untimely rainfall during the growing season.

Technical Abstract:
The high economic potential makes cotton a desirable crop outside of the soils it was native to, which means it sometimes encounters flooding conditions. Cotton is poorly adapted to water-logged soil conditions, considered to be one of the major problems for cotton producers world wide. The objective of this research was to identify differences among the tolerances of modern cotton varieties to flooded soil conditions. A Sharkey clay soil at the University of Missouri Lee Farm in Pemiscot County, Missouri was used for the evaluation. Five seeds of each variety were hand planted in hills spaced 48 inches apart on raised beds on 38 inch rows. A levee of soil was established around the experiment to retain flood water. Each variety was replicated four times in a randomized complete block experimental design. Floods were established to a depth of 8 inches and maintained for at least 72 hours twice during July of both years. The plants were allowed to reach physiological maturity and the resulting cotton was harvested by hand. Differences were observed among cotton varieties in the ability to withstand water-logged soil conditions. More study is needed to identify varieties that perform satisfactorily under flooded soil conditions, if any exist. Furthermore, with the short time that most varieties are commercially marketed, screening methods will be needed in the variety development programs to allow producers to obtain varieties that will produce acceptable yields under such conditions.